Method and device for improving image contrast, LCD TV (liquid crystal display television) set

Abstract

The invention discloses a method and device for improving image contrast and an LCD TV (liquid crystal display television) set. The method for improving image contrast comprises the following steps: adjustment of the brightness of a dynamic backlight: calculating the average gray-scale of all pixels in a frame of image, and according to a congruent relationship between a preset average gray-scaleand the brightness of the backlight, adjusting the brightness of the backlight; gamma compensation: according to a ratio of the original brightness of the backlight to the adjusted brightness, determining a gamma compensation coefficient, then, according to the gamma compensation coefficient, obtaining the gray-scales of all the pixels subjected to compensation in the image; and dynamic pixel gray-scale adjustment: according to a preset dynamic data gray-scale adjustment rule, adjusting the gray-scale of each pixel subjected to gamma compensation so as to obtain the gray-scale of each pixel subjected to adjustment, and displaying the image subjected to adjustment in the brightness of the backlight and the gray-scales of the pixels.

Description

technical field [0001] The invention relates to the technical field of liquid crystal display, in particular to a method and device for improving image contrast, and a liquid crystal television. Background technique [0002] Image contrast refers to the measurement of the different brightness levels between the brightest white and the darkest black in the light and dark areas of an image, reflecting the size of the grayscale contrast of an image. The simple definition is the ratio of the white brightness of the display to the black brightness. Assume that the measured brightness value of a monitor is 200cd / m when it displays a full white screen (255 gray scales) 2 , the measured luminance of a completely black screen (0 grayscale) is 0.5cd / m 2 , then its contrast ratio is 400:1. From the above definition, it can be seen that the higher the contrast of the image, the more vivid the layering of the picture. [0003] At present, in order to improve the optical indicators of...

AI Technical Summary

Problems solved by technology

[0003] At present, in order to improve the optical indicators of LCD TVs, especially large-size LCD TVs, the brightness will be increased to a high level, which is not conducive to energy saving and environmental protection, but also makes black scenes unable to guarantee enough blackness, thereby reducing the display effect of images

Although the dynamic backlight control solves this problem very well, the brightness of the backlight is properly lowered in the dark scene, so that most of the low-grayscale pixels in the dark scene are black enough, but at the same time, the relatively high high-grayscale pixels in the dark scene The output brightness of the pixel is also reduced, which makes the picture that is originally a dark scene darker and affects the quality of the picture.

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